The Homogeneous mixtures of two substances that do not react with each other are called solutions, while inhomogeneous mixtures where the components can be easily distinguished are heterogeneous mixtures, which are called colloids and suspensions. It is necessary, in each case, that there is a substance of a majority proportion (solvent) and another (or others) of lower proportions (solute / solutes), which dissolve in the majority.
The concentrations Each substance can be represented in different ways, one of the simplest is the percentage between solute and solvent. On the other hand, also the molarity (amount of solute per liter of solution) and the parts per million ([cantidad de unidades de soluto por cantidad de unidades de disolución]x106) are options for the representation of concentration.
There may be mixtures whose components individually they are in different states of aggregation and it is, generally, the state of aggregation of the mixture that corresponds to that of the substance that is in greater quantity.
Mixtures of gases and solids
Mixtures between a gas and a solid They can be both homogeneous and heterogeneous, depending on which gas and solid are mixed. For example: airborne volcanic dust, solid aerosol. In these mixtures the gas may be in less quantity and the solid in greater quantity, or the opposite may occur. The case in which a solid dissolves in a gas is not very common, but it usually happens that solid substances such as naphthalene mix with air (which is a mixture of gases), generating a solution in a state of gaseous aggregation. Indeed, gas-solid combinations that have the solid as solute are restricted to powder-type solids that diffuse into gases.
In the other sense, it is more common for a gas to dissolve in a solid, especially in the case of hydrogen as a gas, which is capable of being stored by some metals and used as appropriate. This is a very particular characteristic of the mixture between solids and gases, since much research is carried out to optimize storage.
Compared to the other gases, the hydrogen It is usually much more difficult to store and transport given current resources and technology: this is because the tanks in which they can be stored would have to be much larger, and in its liquid form it must be stored cryogenically at a temperature extremely cold, (thermally insulated tanks are also very expensive).
exist some metals which are especially suitable for hydrogen to be stored. Palladium, for example, can absorb up to 900 times its own volume of hydrogen (at room temperature and atmospheric pressure) in a process that is reversible and can be manipulated. Thus, the challenge for the industry is to make the best possible use of this characteristic property of some metals.
On the other hand, there are heterogeneous mixtures of gases into solids, such as pumice stone, as well as heterogeneous mixtures of solids in gases, for example, airborne particles.
Examples of gas-solid mixtures
- Any kind of smoke (diffusion of solids into a gas)
- Volcanic dust in the air
- Smog particles present in the air
- Hydrogen dissolved in platinum
- Sublimated naphthalene in the air
- Solid spray
- Hydrogen in palladium
- Solid sulfur in air
- Ambient dust in the air
- Pollen scattered in the wind
Other types of mixes
- Gas mixtures
- Mixtures of gas with liquids
- Gas mixtures with solids
- Mixtures of solids with liquids